Global Patent Index - EP 1466473 B1

EP 1466473 B1 20090211 - IMAGE PROJECTOR AND METHOD OF OPERATING SAME

Title (en)

IMAGE PROJECTOR AND METHOD OF OPERATING SAME

Title (de)

BILDPROJEKTOR UND VERFAHREN ZU DESSEM BETRIEB

Title (fr)

APPAREIL DE PROJECTION ET PROCEDE D'EXPLOITATION DUDIT APPAREIL

Publication

EP 1466473 B1 20090211 (EN)

Application

EP 02805868 A 20021218

Priority

  • DE 10200023 A 20020102
  • DE 10220510 A 20020508
  • IB 0205745 W 20021218

Abstract (en)

[origin: WO03056817A1] The invention relates to an image projector with a High-Intensity-Discharge HID lamp (112) and a method of operating it. Such lamps have the disadvantage that their voltaic arc jumps back and forth between different positions at unforeseeable times during operation. This so-called arc jumping has the effect of changing the brightness, i.e. the overall brightness and / or the brightness distribution of the light emitted by the HID lamp (112). For the viewer of an image projected with such a projector, this effect appears as a jolt of this projected image. To avoid such effects for the viewer, it is first proposed according to the invention that changes in the brightness of the light in the image projector's beam path are detected. As soon as a change in brightness caused by an arc jump has been detected, this brightness is reset to a brightness detected at a moment t-2 before the arc jump, in order subsequently to convert it during a predetermined time interval T to the brightness resulting from the arc jump. This resetting must occur so soon after the arc jump, and the conversion so slowly, that the changes in the brightness of the light incident on a picture screen device (118) resulting from the arc jump, the reset, and the conversion are not perceptible to the human eye.

IPC 8 full level

G03B 21/00 (2006.01); G09G 3/20 (2006.01); H04N 5/74 (2006.01); H05B 41/292 (2006.01); H05B 41/38 (2006.01); H05B 41/39 (2006.01); H05B 41/392 (2006.01)

CPC (source: EP US)

H05B 41/2928 (2013.01 - EP US); H05B 41/38 (2013.01 - EP US); H05B 41/392 (2013.01 - EP US)

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SI SK TR

DOCDB simple family (publication)

WO 03056817 A1 20030710; AU 2002356382 A1 20030715; CN 100452852 C 20090114; CN 1611069 A 20050427; EP 1466473 A1 20041013; EP 1466473 B1 20090211; JP 2005513580 A 20050512; TW 200301843 A 20030716; TW I278711 B 20070411; US 2005077841 A1 20050414; US 6979085 B2 20051227

DOCDB simple family (application)

IB 0205745 W 20021218; AU 2002356382 A 20021218; CN 02826614 A 20021218; EP 02805868 A 20021218; JP 2003557202 A 20021218; TW 91137852 A 20021230; US 50050604 A 20040629